Http Handlers to handle Images

HTTP handlers implement the following two methods:
1) ProcessRequest: called to process http requests and
2) IsReusable which indicates whether this instance of http handler can be reused for fulfilling another requests of the same type.

In your website Add new Item Generic Handler and name it as ImageHandler.ashx

Here is ImageHandler.ashx file

<%@ WebHandler Language="C#" Class="ImageHandler" %>

using System;
using System.Web;
using System.IO;

public class ImageHandler : IHttpHandler
{

public void ProcessRequest(HttpContext context)
{
string sImageFileName = "";
int iThumbSize = 0;
decimal dHeight, dWidth, dNewHeight, dNewWidth;

sImageFileName = context.Request.QueryString["img"];
iThumbSize = Convert.ToInt32(context.Request.QueryString["sz"]);

System.Drawing.Image objImage = System.Drawing.Bitmap.FromFile(System.Web.HttpContext.Current.Server.MapPath("Image Path" + sImageFileName));
if (sImageFileName != null)
{
if (iThumbSize == 1)
{

dHeight = objImage.Height;
dWidth = objImage.Width;
dNewHeight = 120;
dNewWidth = dWidth * (dNewHeight / dHeight);
objImage = objImage.GetThumbnailImage((int)dNewWidth, (int)dNewHeight, new System.Drawing.Image.GetThumbnailImageAbort(callback), new IntPtr());
}
if (iThumbSize == 2)
{

dHeight = objImage.Height;
dWidth = objImage.Width;
dNewHeight = 200;
dNewWidth = dWidth * (dNewHeight / dHeight);
objImage = objImage.GetThumbnailImage((int)dNewWidth, (int)dNewHeight, new System.Drawing.Image.GetThumbnailImageAbort(callback), new IntPtr());
}

MemoryStream objMemoryStream = new MemoryStream();
objImage.Save(objMemoryStream, System.Drawing.Imaging.ImageFormat.Jpeg);
byte[] imageContent = new byte[objMemoryStream.Length];
objMemoryStream.Position = 0;
objMemoryStream.Read(imageContent, 0, (int)objMemoryStream.Length);
context.Response.ContentType = "image/jpeg";
context.Response.BinaryWrite(imageContent);
}
}


private bool callback()
{
return true;
}
public bool IsReusable
{
get
{
return false;
}
}

}

Following is the way to write it..

<img id="Image1" src='../ImageHandler.ashx?img=ImageName&sz=1' />